Electric propulsion motor mounting and drive means

ABSTRACT

A motor mounting and drive means for an electric propulsion motor of an electric lift truck, or the like, which reduces road shock into the motor as well as reduces motor vibration into the vehicle chassis. The mounting and drive arrangement comprise a pair of support brackets which are rigidly secured to the opposite end faces of the electric propulsion or traction motor and resiliently secured to the vehicle frame to suspend the motor in a horizontal position subjacent a compartment of the vehicle for housing the batteries for supplying electrical power to the motor. In addition a universal joint is employed to couple the drive shaft of the electric motor to a differential for driving one set of wheels of the vehicle.

United States Patent Gawlik et al.

1451 Nov. 20, 1973 1 ELECTRIC PROPULSION MOTOR MOUNTING AND DRIVE MEANS[73] Assignee: Towmotor Corporation, Cleveland,

Ohio

[22] Filed: Sept. 27, 1971 [21] Appl. No.: 184,002

Brooks 180/64 M 180/57 X 3/1913 9/1924 Holy Primary ExaminerBenjaminHersh Assistant ExaminerDavid M. Mitchell Attorney-Fryer, Tjensvold,Feix, Phillips & Lempio 57 ABSTRACT A motor mounting and drive means foran electric propulsion motor of an electric lift truck, or the like,which reduces road shock into the motor as well as reduces motorvibration into the vehicle chassis. The mounting and drive arrangementcomprise a pair of support brackets which are rigidly secured to theopposite end faces of the electric propulsion or traction motor andresiliently secured to the vehicle frame to suspend the motor in ahorizontal position subjacent a compartment of the vehicle for housingthe batteries for supplying electrical power to the motor. In addition auniversal joint is employed to couple the drive shaft of the electricmotor to a differential for driving one set of wheels of the vehicle.

3 Claims, 3 Drawing Figures INVENTORS EDWARD F. GAWLIK RICHARD A.SCHWEHR 9/ w MM i ATTORNEYS PATENIEDunvzo I975 SHEET 3 BF 3 BY y- 2 j;7) TORNEYS ELECTRIC PROPULSION MOTOR MOUNTING AND DRIVE MEANS BACKGROUNDOF THE INVENTION Heretofore the electric propulsion or traction motor ofelectric lift trucks has typically included an integral base, which inturn is rigidly bolted to the truck frame to support the motor in ahorizontal position. The drive shaft of the motor has been splined orotherwise directly coupled to the input shaft of a differential fordriving the front wheels of the truck. With such a rigid mounting anddirect drive arrangement road shock has been imparted to the motorshaft, and as a result, motor life has been minimized. In addition,motor vibration has been undersirably transmitted to the vehicle chassiswith such previous electric motor mounting and drive arrangements.

SUMMARY OF THE INVENTION The present invention relates to electric lifttrucks and the like, and is more particularly directed to an improvedresilient mounting and flexible drive arrangement for the electricpropulsion motor thereof.

It is an object of the present invention to provide an improved electricpropulsion motor mounting and drive arrangement for an electric lifttruck which effectively reduces the transmission of road shock to themotor and thereby materially extends the life thereof.

A further object of the invention is the provision of an electric motormounting and drive arrangement of the class described whichsubstantially reduces the transmission of motor vibration into thevehicle chassis In the accomplishment of the foregoing and other objectsand advantages, an electric motor mounting and drive arrangement inaccordance with the present invention generally includes a pair ofsupport brackets respectively rigidly secured adjacent the opposite endsof an electric propulsion motor of an electric lift truck, means forresiliently securing the support brackets to horizontal members of thetruck frame to resiliently suspend the motor in a horizontal position,and a universal joint coupling the rotary drive shaft of the electricpropulsion motor to a differential carried by the truck frame fordriving one set of the truck wheels.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view ofan electric lift truck embodying an electric propulsion motor mountingand drive arrangement in accordance with the present invention.

FIG. 2 is a plan view of the mounting and drive arrangement.

FIG. 3 is an exploded perspective view of the mounting arrangement.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTIONReferring now to FIG. I in detail, there is shown an electric lift truck11 having a frame including a pair of transversely spaced side panels12. Sets of front and rear wheels 13 and 14 are joumalled at theopposite ends of the frame in a conventional manner, and a differential16 is carried by the frame and coupled to the front wheels 13 inaccordance with usual practice.

Drive power to the front wheels 13 is facilitated by means of anelectric traction or propulsion motor 17 mounted to the truck frame in ahorizontal position subjacent a battery compartment (not shown) forhousing batteries for supplying electrical power to the motor. The motor17 includes a splined rotary drive shaft 18 which is ultimately coupledto the input shaft 19 of differential 16 to thereby transmit motivepower to the front wheels 13.

Heretofore the electric propulsion motor of an electric lift truck ofthe general type outlined above has typically included an integral basewhich has been rigidly bolted to members of the truck frame tofacilitate mounting thereof. In addition the usual practice with anelectric propulsion motor has been to directly connect the motor driveshaft to the input shaft of the differential associated with the frontwheels. Such a conventional arrangement has resulted in shortened lifeof the propulsion motor by virtue of road shock being imparted to thedirect coupled drive shaft of the rigidly mounted propulsion motor, andconversely the arrangement has resulted in the transmission of motorvibration into the truck frame.

The foregoing disadvantages are obviated in accordance with theparticularly salient aspects of the pres ent invention by means of aresilient motor mounting and flexible drive coupling which serve toreduce the transmission of road shock to the electric propulsion motor17 and the transmission of motor vibration to the truck frame.

In this regard, the electric propulsion motor 17 is not provided with anintegral base to facilitate rigid bolting of the motor to the frame oftruck I 1. Rather, a pair of support brackets 21 and 22 are rigidelysecured to the motor respectively adjacent the front and rear endsthereof, and means are provided to resiliently attach the brackets tothe truck frame in a manner to resiliently suspend the motor therefromin a horizontal position.

In addition, a universal joint 23 is employed to couple the splineddrive shaft 18 of the electric propulsion motor to input shaft 19 ofdifferential 16. The brackets and resilient attachment means, and theuniversal joint thereby respectively comprise the motor mounting andflexible drive coupling of previous mention.

Considering now the resilient motor mounting in more detail, the frontsupport bracket 21 includes a generally rectangular end plate 24preferably having an upper edge defined by a horizontal central portion26 and outer portions 27 oppositely downwardly inclined therefrom, asbest shown in FIG. 3. Bracket 21 also includes an upper plate 29integral with end plate 24 and projecting right angularly therefromadjacent its upper edge.

The upper plate is generally conformed to the configuration of the upperedge of the end plate such that the upper plate includes a horizontalcentral portion 31 with outer portions 32 laterally oppositelydownwardly inclined therefrom. The leading edge of upper plate 29 isbest provided with a central dovetail notch 34 defined by convergingrearwardly extending angular edge portions 36 of outer plate portions 32which terminate in the leading edge 38 of plate central portion 31 whichis parallel to end plate 24. The lower side edges of outer portions 32of upper plate 29 are provided with laterally outwardly projectinghorizontal ears 39 adjacent the leading edge thereof, which ears areparallel to the central portion 31 of the upper plate.

Rigid attachment of bracket 21 to the motor 17 is facilitated by meansof bolts 42 traversing apertures 43 provided in end plate 24 andthreadably engaging circumferentially spaced taps 44 formed in the frontend face of the motor to also facilitate bolted attachment of a frontend cover plate 46 thereto. With the bracket 21 thus rigidly secured tothe front end face of the motor, the upper plate 29 engages the upperperiphery of the motor with the horizontal ears 39 projecting laterallyoutward therefrom.

The ears facilitate resilient attachment of the bracket in a mannersubsequently described to a pair of transverse lugs 47 oppositelyprojecting inwardly from the side panels 12 of the truck frame, as bestshown in FIG. 2.

The rear support bracket 22 is generally similar to the front bracket 21and includes a rectangular end plate 48 and integral upper plate 49projecting rightangularly from the upper edge thereof. Unlike the upperplate 29 of the front bracket 21, the upper plate 49 of the rear bracketis planar. The leading edge of upper plate 49 is similarly preferablyprovided with a central dovetail notch 51 defined by convergingrearwardly extending angular edge portions 52 terminating at theopposite ends of an edge portion 54 parallel to end plate 48. The outerside edges of upper plate 49 are formed with laterally outwardlyprojecting ears 56 adjacent the leading edge thereof.

Rigid attachment of bracket 22 to the motor 17 is facilitated by meansof bolts 58 traversing aperture 59 provided in end plate 48 andthreadably engaging circumferentially spaced taps formed in the rear endface of the motor. With the bracket 22 rigidly secured to the rear endface of the motor, the upper plate 49 engages the upper periphery of acircumscribing cowl 60 of the motor, which cow] is provided with theelectrical input terminals 61 of the motor (see FlG. 2). The horizontalears 56 facilitate resilient attachment of bracket 22 in a mannersubsequently described to a pair of transverse lugs 62 oppositelyprojecting inwardly from the side panels 12 of the truck frame.

With regard to the resilient attachment of the brackets 21 and 22 to theframe lugs 47 and 62, it is to be noted that the lugs are respectivelyprovided with apertures 63 and 64 which are traversed by tubularresilient pads 66 and 67 of rubber, or the like, having enlarged heads68 and 6? which bear against the upper surfaces of the lugs. Bolts 71extend through apertures 72 provided in ears 39, while bolts 73 extendthrough apertures 74 provided in ears 56. The bolts 71 and 73 thereafterextend through the bores of the pads 66 and 67 which traverse the lugapertures 63 and 64 and threadably receive nuts 75 and 76 which bearagainst the lower surfaces of the lugs 47 and 62.

The bracket ears 39 and 56 thus bear against the upper ends of the padheads 68 and 69, although washers and shims, as generally indicated at77, may be interposed if desired. The resiliently mounted brackets 21and 22 thus serve to resiliently suspend the electric propulsion motor17 from the truck frame in a horizontal position.

The resilient motor mounting in conjunction with the universal joint 23serve to effectively absorb road shock and motor vibration.

Although the invention has been hereinbefore described and illustratedin the accompanying drawings with respect to a single preferredembodiment, it will be appreciated that various modifications andchanges may be made therein without departing from the true spirit andscope of the invention, and thus it is not intended to limit theinvention except by the terms of the appended claims.

What is claimed is:

1. In a vehicle including a frame, sets of front and rear wheelsjournalled at the opposite ends of said frame, a differential carried bysaid frame and coupled to one of said sets of wheels, and an electricpropulsion motor having a rotary drive shaft for coupling to an inputshaft of said differential, the combination comprising a pair of supportbrackets respectively rigidly secured adjacent the opposite ends of saidelectric propulsion motor, means for resiliently securing said bracketsto said frame to suspend said motor in a horizontal position, and drivemeans for coupling said drive shaft of said motor to said input shaft ofsaid differential, further defined by said brackets being rigidly boltedto the opposite end faces of said motor and having oppositely laterallyprojecting horizontal ears for securance to inwardly transverselyprojecting horizontal members of said frame, said resilient securingmeans comprising resilient pads traversing apertures in said horizontalmembers and having enlarged heads engaging the upper surfaces thereof,bolts extending through apertures in said ears and traversing said pads,and nuts threadably secured to said bolts and bearing against the lowersurfaces of said horizontal members, said ears bearing against saidheads of said pads, further defined by said brackets having end platesand integral rightangularly projecting upper plates, said end plateshaving apertures therethrough, said upper plates having said earsprojecting from the opposite side edges thereof, and bolts traversingsaid apertures of said end plates and threadably engagingcircumferentially spaced taps in the end faces of said motor, said upperplates engaging the upper periphery of said motor.

2. The combination of claim 1, further defined by said drive meanscomprising a universal joint,

3. The combination of claim 2, further defined by a first of saidbrackets having a generally rectangular end plate with an upper edgedefined by a horizontal central portion and outer portions oppositelydownwardly inclined therefrom, said first bracket having an upper platesubstantially conformed to said upper edge of said end plate thereof andincluding a horizontal central portion with outer portions laterallyoppositely downwardly inclined therefrom, said upper plate of said firstbracket having a central dovetail notch defined by converging rearwardlyextending angular edge portions of said outer portions of said upperplate of said first bracket terminating in the leading edge of saidcentral portion thereof, said ears of said first bracket laterallyoutwardly projecting from the lower side edges of said outer portions ofsaid upper plate of said first bracket adjacent the leading edgethereof, and a second of said brackets having a rectangular end plateand a planar upper plate having a central dovetail notch in the leadingedge thereof, said ears of said second bracket laterally outwardlyprojecting from the opposite said edges of said upper plate of saidsecond bracket adjacent the leading edge thereof.

1. In a vehicle including a frame, sets of front and rear wheelsjournalled at the opposite ends of said frame, a differential carried bysaid frame and coupled to one of said sets of wheels, and an electricpropulsion motor having a rotary drive shaft for coupling to an inputshaft of said differential, the combination comprising a pair of supportbrackets respectively rigidly secured adjacent the opposite ends of saidelectric propulsion motor, means for resiliently securing said bracketsto sAid frame to suspend said motor in a horizontal position, and drivemeans for coupling said drive shaft of said motor to said input shaft ofsaid differential, further defined by said brackets being rigidly boltedto the opposite end faces of said motor and having oppositely laterallyprojecting horizontal ears for securance to inwardly transverselyprojecting horizontal members of said frame, said resilient securingmeans comprising resilient pads traversing apertures in said horizontalmembers and having enlarged heads engaging the upper surfaces thereof,bolts extending through apertures in said ears and traversing said pads,and nuts threadably secured to said bolts and bearing against the lowersurfaces of said horizontal members, said ears bearing against saidheads of said pads, further defined by said brackets having end platesand integral right-angularly projecting upper plates, said end plateshaving apertures therethrough, said upper plates having said earsprojecting from the opposite side edges thereof, and bolts traversingsaid apertures of said end plates and threadably engagingcircumferentially spaced taps in the end faces of said motor, said upperplates engaging the upper periphery of said motor.
 2. The combination ofclaim 1, further defined by said drive means comprising a universaljoint.
 3. The combination of claim 2, further defined by a first of saidbrackets having a generally rectangular end plate with an upper edgedefined by a horizontal central portion and outer portions oppositelydownwardly inclined therefrom, said first bracket having an upper platesubstantially conformed to said upper edge of said end plate thereof andincluding a horizontal central portion with outer portions laterallyoppositely downwardly inclined therefrom, said upper plate of said firstbracket having a central dovetail notch defined by converging rearwardlyextending angular edge portions of said outer portions of said upperplate of said first bracket terminating in the leading edge of saidcentral portion thereof, said ears of said first bracket laterallyoutwardly projecting from the lower side edges of said outer portions ofsaid upper plate of said first bracket adjacent the leading edgethereof, and a second of said brackets having a rectangular end plateand a planar upper plate having a central dovetail notch in the leadingedge thereof, said ears of said second bracket laterally outwardlyprojecting from the opposite said edges of said upper plate of saidsecond bracket adjacent the leading edge thereof.